Although garnets can be identified at a glance, it is not easy to determine what kind of garnet is because the composition of garnet is complex and contains many types. Garnet is a gem series composed of two series and six subspecies. The general molecular formula is R3M2 (SIO4) 3, R stands for divalent elements (calcium, magnesium, iron, manganese), and M stands for trivalent elements (aluminum, iron, chromium), different combinations of R and M form different garnet subspecies, and some garnets are even garnet mixtures of different combinations.
Although different kinds of garnets have different colors, refractive index, specific gravity and hardness are also slightly different, but all garnets are isocrystalline, single refraction gemstones, without dichroism and polarization. Keeping this common property in mind is useful for garnet identification.
Common gem garnet and its characteristic color:
◆ Almandine, maroon
◆ Spessartine, red
◆ Spessartine, orange-yellow
◆ Grossmantine, yellow-green
◆ Andandrite, green
◆ Pyrope, rose red
◆ Garnet, emerald green
As a general appreciator or customer, there is no need to determine the specific species of garnet, as long as they know that they are indeed garnets. There are not many gems similar to garnet on the market, mainly ruby, red zircon, spinel, synthetic yttrium aluminum garnet, gadolinium gallium garnet and glass imitation.
The method of distinction is: rhododendron and red zircon both have dichroism, red zircon also has a strong double shadow, and garnet has no duality, so it is easy to distinguish from pomegranate; spinel is generally lighter in color, and detailed identification To use the instrument. All kinds of natural garnets have some flaws or crystalline inclusions (such as acicular gold stones, some gas-liquid two-phase inclusions, etc.), while Y . A . G., G . G . G. and glass are often very clean, or There are spherical breadcrumb-like bubbles, strong red under Chelsea, etc. In fact, for some specific garnets, it can also have its own unique characteristics. For example, demantoid (a green variant of andandrite) often has "horsetail-shaped" fiber inclusions, which can be seen by experienced people at a glance see.
Identification key: no pleochroism, often with natural body.
Evaluation of garnet: garnet is a common gemstone, but among them, emerald green and transparent ones are also rare varieties. The most important thing to evaluate garnet is the color of the gemstone, which should be bright and pure; secondly, the transparency should be high, so that the processed gemstones can be bright and "fire"; thirdly, the flaws should be few, and the style should be beautiful; value is less affected. It should be noted that there are also starlight and cat's eye gemstones in garnet. If the color is correct, the starline or eyeliner is good, it is a variety with high value.
Evaluation key: the color is pure, crystal clear and transparent, with few blemishes.
